XR21B1411IL-0A-EB Datasheet, PDF (14/30 Pages) Exar Corporation – ENHANCED 1-CH FULL-SPEED USB UART

XR21B1411
ENHANCED 1-CH FULL-SPEED USB UART
TABLE 5: B1411 REGISTERS
REV. 1.2.0
ADDRESS
REGISTER NAME
BIT-11
BIT-
10
BIT-9 BIT-8 BIT-7 BIT-6 BIT-5 BIT-4
BIT-3
BIT-2 BIT-1 BIT-0
0xC11 GPIO_INT_MASK
0
0
0
0
0
0
GPIO GPIO GPIO GPIO GPIO GPIO
5
4
3
2
1
0
0xC12 CUSTOMIZED_INT 0
0
0
0
0
0
0
0
0
0
0 EN
0xC14 PIN_PULLUP_EN
0
0
0
0
TX
RX
GPIO GPIO GPIO GPIO GPIO GPIO
5
4
3
2
1
0
0xC15 PIN_PULL-
DOWN_EN
0
0
0
0
TX
RX
GPIO GPIO GPIO GPIO GPIO GPIO
5
4
3
2
1
0
0xC16 LOOPBACK
0
0
0
0
0
0
0
0
0
DTR_ RTS_ TX_
DSR CTS _RX
0XC80 TX_FIFO_RESET
0
0
0
0
0
0
0
0
0
0
0 TX
0xC81 TX_FIFO_COUNT 0
0
0
0
COUNT
0XCC0 RX_FIFO_RESET 0
0
0
0
0
0
0
0
0
0
0 RX
0xCC1 RX_FIFO_COUNT 0
0
0
COUNT
0xCC2 RX_FI-
FO_LOW_LA-
TENCY
0
0
0
0
0
0
0
0
0
0
0 EN
0xD02 WIDE_MODE
0
0
0
0
0
0
0
0
0
0
0 EN
3.1.1 B1411 Register Descriptions
Note that all register reset default values are ’0’ unless otherwise specified.
3.1.1.1
CUSTOM_DRIVER (Write Only)
CUSTOM_DRIVER[0]: Active
This register holds the flag to determine which device driver is used (custom or CDC driver). For proper
operation, a custom driver must set the ACTIVE bit prior to sending any of the 4 CDC_ACM commands that
the B1411 supports.
 Logic 0 = Informs the B1411 that the standard CDC_ACM driver is being used. Values from the
CDC_ACM_xxx_xxxx registers will be loaded into their non-CDC_ACM equivalents.
 Logic 1 = Informs the B1411 that a custom driver is being used. Values from CDC_ACM_xxx_xxxx registers
are not used.
CUSTOM_DRIVER[11:1]: Reserved
These bits are reserved and should remain ’0’.
3.1.1.2
CDC_ACM_FLOW_CONTROL Register Description (Read / Write)
The contents of this register, if programmed, are used to overwrite the FLOW_CONTROL register at address
0xC06 when a CDC command is sent from a standard CDC-ACM driver to the B1411 device. Note that this
register can only be programmed from the OTP. Since a standard CDC_ACM driver is unaware of UART
registers in the B1411, this register may be utilized to program UART settings from power-up. When a custom
driver is used, the custom driver should program these settings directly into the FLOW_CONTROL register.
Bit fields in this register are the same as those in the FLOW_CONTROL register. Refer to “Section 3.1.1.7,
FLOW_CONTROL Register Description (Read / Write)” on page 15.
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